Process of casting finished pinions or gear-wheels.



L. J. CRECELIUS. 'PROCESS 0F CAS FINISHED PINIDNS 0B GEAR WHEELS.

Y Application Jxvmu B, 1901. Renewed Oct. 2D, 1902.)

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No. 716,870A

Patented'ec. 305 1902.v L. J. CRECELIUS; v PROCESS 0F CASTING FINISHEDPINIUNS 0R GEAR WHEELS. Y

(Applicatian fIedJune 8, 1901. Renewed Oct.-20, 1902.)

(No Model.)

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UNITED STATES PATENT OEEICE.

LOUIS J. OREOEI.|IUS,,VOF` ST. LOUIS,A MISSOURI, ASSIGNOR OFONE-I-IALFTO WILLIAM GRAYSON, OF ST. LOUIS, MISSOURI.

PROCESS OF CASTING FINISHED PINIONS OR GEAR-WHEELS.

SPECIFICATION forming part Of Letters Patent N o. 716,870, dated.December 30, 1902. Application tiled June 8, 1901. Renewed Gotoher 20,1902. Serial No. 128,083. (No model.)

To a/ZZ whom tm/ty concern,.-

Beit known that I, LoUIs J. CRECELIUS, of the city of St. Louis, Stateof Missouri, have invented certain new and useful Improvements inProcesses of Casting Finished Pinions or Gear-Wheels, of which thefollowing is a full, clear, and exact description, referenceV A furtherobject of my invention is to pro' duce such pinions and gear-Wheels withan accurately-finished face primarily and solely by the castingoperation.

A further object is to produce said pinions and gear-wheels devoid ofthe usual shrinkage, and yet having accurately spaced and finished teethand other accu rately-nished parts primarily and Vsolely by the castingoperation.

A further Objectis to produce said pinions and gear-wheels having ashell or skeleton of metal, such as bronze or steel, and the same havingcast within themselves'an annular core of refractory material whichshall act to reinforce or strengthen said shell and greatly lightenandcheapen the same.

improved molding-flask made use of.

Figure l is a sectional side elevation of the Fig. 2 is a similar viewhaving the master-pattern in position therein and also showing theimproved rammer in use. Fig. 3 is a plan view of the said ask. Fig. i isaplanvicw of the parts shown in Fig. 2. Fig. 5 is a sectional sideelevation showing the flask' after the same has been rammed andillustrating the said master-pattern in the act of being Withdrawn. Fig.6 is a similar view of the rammed ask having the annular core supportedtherein. Fig. 7 is a view identical with the last,

except that it has a'tapered mandrel in posii tion therein. Fig. 8 is aview identical to the last with the exception that the gate and spreaderare applied to thelfiask and the casting has been poured, the same beingstill located Within the flask. Fig. 9 is a sectional plan view of afinished pinion or gear-Wheel.

l indicates a cylindrical ask,preferably Ina-de of metal, and fittedwithin its-lowerend isa head 2, the inner face of which is bored andturned accurately and highly polished to act as a mold-surface for oneface of the pinions or gear-wheels to pbe cast thereon. Within this daskI next placca preferably metallic master-pattern 3, having a lengthconsiderably in excess of the depth of said flask and having machine-cutteeth Llof the properpitch and cou ntersunk at its lower end, whereby itmay be accurately fitted upon the raised center 5 of said head 2 andwhereby the act of placing said pattern will also center itWith'relation to said center. Next I proceed to ram the ask in themanner shown in Fig. 2 by placing a body of refractory pulverulentmaterial 6--say refractory carbon-Within the annular space about saidmaster-pattern and ramming the same by means of the annular rammer 7.Said rammer 7 has an external diameter corresponding to the internaldiameter of said ask and is vprovided with a series of internal radialprojections 8, which occupy the space betweenf the teeth 4 of saidmaster-pattern during the act of ramming. Said rammer is provided withopposite vertical handles 9, .by means of which it may be lifted duringuse. After the ask has been fully filled the master-pattern 3 iswithdrawn, as shown in Fig. 5, and then I place within the moldV soformed an annular core 10, preferably made of some refractory material,such as common tire-clay, and this hassuitable projections 1l at itsends for supporting it within the mold, so that when the .metal ispoured said metal may pass upon all sides of said core. Said core 10 hasa tapered internal passage, in which is next placed the tapered metallicmandrel 12, which latter accurately iits said tapered passage, and whichmandrel is pro vided with a lateral projection 13, which projects towarda corresponding recess in said core, so as to form a key-seat in thepinion or IOO gear to be cast. Said mandrel may of course be accuratelyfinished and highly polished and preferably provided with a coating ofsuitable fireproof lubricant. I prefer graphitic carbon. It will benoted that said mandrel fits accurately the center bore of said head 2,which acts as a rigid support therefor. Mounted upon the upper end ofsaid mandrelis a conical spread er 14, and mounted upon the upper faceof the mold as finished is a common gate 15. The mold is now ready to bepoured. However, prior to pouring, the entire mold, as shown in Fig. 8,is lifted b v means of its projecting ears 16 and placed within asuitable furnace and heated to about 900 Fahrenheit and then quicklywithdrawn and the metal poured therein, and while the metal is stillfluid within the said mold I apply pressure thereon by means of anycommon press, and thereby slightly compress said fluid metal. Thiscompression solidifies the iiuid metal in the mold, and thereby causesevery part of the casting to shrink uniformly. Finally the gate 15 isremoved, the casting is removed from the mold, and its upper end issawed off at a suitable point. The finished product is shown in sectionin Fig. 9. The finished product is indicated in Fig. 9 by the numeral20, and it is provided with the filling or core 10, as above described,and has of course the tapered bore 21, having the keyseat 22, whichlatter is formed by the lateral projection 13 of the said metallicmandrel 12.

Of course it will be understood that the mandrel 12 should be removedafter'the end of the casting has been sawed off.

The advantages possessed by my invention are as follows:

First. I obviate the usual verylarge amount of labor required inproducing machine-cut pinions and gears, and I produce a finishedarticle direct from the mold.

Second. By my process I retain the strongest of the metal, which, as iswell known, is always on the surface of castings.

Third. By making use of the annular strengthening-core Within thecasting I am thus enabled to dispense with fully one-third of the metalusually required and substitute therefor much lighter and cheapermaterial. The advantage of lightness `in a high-speed pinion is wellunderstood. In this connection I desire to state that I have found thatin a core made of fire-clay or similar substances when burned prior toplacing within the mold and then reheated, as described, the liquidmetal will fill all the interstices of said core and firmly adhere, andthus make a solid mass of the core. The article thus cast will be foundpractically as strong as if it had Ybeen cast of solid metal.

Fourth. By slowly pouring the liquid metal into the heated mold, whichpermits all gases to develop and be discharged as the pouring proceeds,thereby preventing all blow-holes, honeycombs, dac., and assures anabsolutely dense casting.

I do not herein claim the product of my improved process, as I have madethe same the subject-matter of a copending application, tiled October 7,1901, Serial No. 77,790.

I claiml. The herein-described process of casting finished pinions andgear-Wheels, which consists in rst, forming a flask with a metallic headat its lower end turned and polished accurately and provided with araised center 5 and a central bore; second, forming a metallicmaster-pattern with accurately-finished peripheral teeth and acounter-sunk recess at its lower end; third, mounting said masterpatternin said flask, so that said mold-surface will fit within saidcountersunk recess of the master-pattern; fourth, placing a body ofrefractory carbon Within the annular space about said master-pattern andsimultaneously ramming said refractory carbon into all the spacesbetween the teeth of said master-pattern by means of an annular rammer;fifth, removing said rammer; sixth, withdrawing said master-pattern;seventh, mounting Within the central bore of said flask-head a taperedmetallic mandrel provided with a lateral projection to form a key-seatin the casting; eighth, mounting aconical spreader upon the upper end ofsaid metallic mand rel; ninth, mounting a gate upon the upper face ofthe finished mold; tenth, heating the mold to about 900o Fahrenheit, andpouring molten metal into the mold while the same is thus heated;substantially as specified.

2. The herein-described process of casting finished pinions andgear-wheels, which consists in rst, forming a iask with a metallic headat its lower end turned and polished accurately and provided with araised center 5 and a central bore; second, forming a metallicmaster-pattern with accurately-finishedperipheral teeth and acountersunk recess at its lower end; third, mounting said master-patternin saidfiask, so that said mold-surface will fit within said countersunkrecess of the master-pattern; fourth, placing a body of refractorycarbon within the annular space about said master-pattern andsimultaneously ramming said refractory carbon in all the spaces betweenthe teeth of said masterpattern by means of an annular rammer; fifth,removing said rammer; sixth, withdrawing said master-pattern;seventh,mount ing within the central bore of said ask-head a taperedmetallic mandrel provided with a lateral projection to form a key-seatin the casting; eighth, mounting a conical spreader upon the upper endof said metallic mandrel; ninth, mounting a gate upon the upper face ofthe nished mold; tenth, heating the mold to about 900 Fahrenheit, andpouring molten metal into the mold while the same is thus heated; andfinally, applying pressure to the molten metal while in a fluid statewithin said mold; substantially as specified.

3. The herein-described process of casting finished pinions andgear-wheels, which con- IOO siste in rst, forming a flask With ametallic head at its lower end turned and polished accurately andprovided with a raised center 5 and a central bore; second, forming ametallic master-pattern With accurately-finished peripheral teeth and aeountersunk recess at its lower end; third, mounting said master-patternin said flask, so that said mold-surface will t Within said countersunkrecess of the master-pattern; fourth, placing a body of refractorycarbon Within the annular space about said master-pattern andsimultaneously ramming said refractory carbon into ail the spacesbetween the teeth of said master-pattern by means of an annular rammer;fifth, removing said rammer; sixth, Withdrawing said master pattern;seventh, placing Within the mold an annular core of fire-clay, havingsuitable projections at its ends for LOUIS J. CRECELIUS.

Witnesses:

ALFRED A.'EICKS, J oHN C. HIGDoN.

